Vehicle route modification to improve vehicle location information

ABSTRACT

An illustrative example embodiment of a system for controlling a vehicle includes at least one sensor configured to detect at least one localization reference and at least one processor configured to determine a location of the vehicle with a first precision based on an indication from the at least one sensor while the vehicle is traveling in a first lane of a roadway. The processor is configured to determine that at least one characteristic of the first precision is below a threshold and, based on the at least one characteristic being below the threshold, maneuver the vehicle to a second lane of the roadway.

TECHNICAL FIELD

This description relates to modifying a vehicle route to improve vehicle location information.

BACKGROUND

Autonomous vehicles can travel without requiring a human driver. There are various technologies involved in controlling the vehicle to follow a route to an intended destination. One aspect of controlling the vehicle includes determining the vehicle location along the route. Existing technologies for determining the vehicle location are based on, for example, information from GNSS satellite signals, map data, and on-vehicle sensor observation of the environment near the vehicle. While such technologies are useful, there are situations in which the availability of such information is limited resulting in potentially decreased precision in vehicle location information.

SUMMARY

An illustrative example embodiment of a system for controlling a vehicle includes at least one sensor configured to detect at least one localization reference and at least one processor configured to determine a location of the vehicle with a first precision based on an indication from the at least one sensor while the vehicle is traveling in a first lane of a roadway. The processor is configured to determine that at least one characteristic of the first precision is below a threshold and, based on the at least one characteristic being below the threshold, maneuver the vehicle to a second lane of the roadway.

An illustrative example embodiment of a computer-implemented method includes determining a location of a vehicle with a first precision based on at least one localization reference while the vehicle, which includes at least one processor and at least one sensor, is traveling in a first lane of a roadway. The method includes determining that the first precision has at least one characteristic that is below a threshold and, based on the first precision being below the threshold, maneuvering the vehicle, using the at least one processor, to a second lane of the roadway.

Another illustrative example embodiment of a system for controlling a vehicle includes at least one sensor configured to detect at least one localization reference. A processor is configured to determine that at least one obstruction near the vehicle is preventing the at least one sensor from detecting the at least one localization reference while the vehicle is traveling in a lane of a roadway and, based on the determination, alter a speed of the vehicle while in the lane to change a position of the vehicle relative to the obstruction until the obstruction no longer prevents the sensor from detecting the at least one localization.

These and other aspects, features, and implementations can be expressed as methods, apparatus, systems, components, program products, means or steps for performing a function, and in other ways.

These and other aspects, features, and implementations will become apparent from the following descriptions, including the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. A1 shows an example of an autonomous vehicle having autonomous capability.

FIG. A2 illustrates an example “cloud” computing environment.

FIG. A3 illustrates a computer system.

FIG. B1 shows an example architecture for an autonomous vehicle.

FIG. C1 shows an example of inputs and outputs that may be used by a perception module.

FIG. C2 shows an example of a LiDAR system.

FIG. C3 shows the LiDAR system in operation.

FIG. C4 shows the operation of the LiDAR system in additional detail.

FIG. D1 shows a block diagram of the relationships between inputs and outputs of a planning module.

FIG. D2 shows a directed graph used in path planning.

FIG. E1 shows a block diagram of the inputs and outputs of a control module.

FIG. E2 shows a block diagram of the inputs, outputs, and components of a controller.

FIG. F1 is a flowchart diagram summarizing an example embodiment of a method of controlling a vehicle.

FIG. F2 schematically illustrates an example scenario including maneuvering a vehicle to improve a vehicle location determination based on lane markings.

FIG. F3 schematically illustrates another example scenario including maneuvering a vehicle to improve a vehicle location determination based on lane markings.

FIG. F4 schematically illustrates another example scenario including maneuvering a vehicle to improve a vehicle location determination based on lane markings.

FIG. F5 schematically illustrates selected features of an example embodiment that includes using satellite signals as localization reference information.

FIG. F6 schematically illustrates an example scenario including maneuvering a vehicle to improve a vehicle location determination based on satellite signals.

FIG. F7 schematically illustrates another example scenario including maneuvering a vehicle to improve a vehicle location determination based on satellite signals.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the present invention.

In the drawings, specific arrangements or orderings of schematic elements, such as those representing devices, modules, instruction blocks and data elements, are shown for ease of description. However, it should be understood by those skilled in the art that the specific ordering or arrangement of the schematic elements in the drawings is not meant to imply that a particular order or sequence of processing, or separation of processes, is required. Further, the inclusion of a schematic element in a drawing is not meant to imply that such element is required in all embodiments or that the features represented by such element may not be included in or combined with other elements in some embodiments.

Further, in the drawings, where connecting elements, such as solid or dashed lines or arrows, are used to illustrate a connection, relationship, or association between or among two or more other schematic elements, the absence of any such connecting elements is not meant to imply that no connection, relationship, or association can exist. In other words, some connections, relationships, or associations between elements are not shown in the drawings so as not to obscure the disclosure. In addition, for ease of illustration, a single connecting element is used to represent multiple connections, relationships or associations between elements. For example, where a connecting element represents a communication of signals, data, or instructions, it should be understood by those skilled in the art that such element represents one or multiple signal paths (e.g., a bus), as may be needed, to effect the communication.

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one of ordinary skill in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.

Several features are described hereafter that can each be used independently of one another or with any combination of other features. However, any individual feature may not address any of the problems discussed above or might only address one of the problems discussed above. Some of the problems discussed above might not be fully addressed by any of the features described herein. Although headings are provided, information related to a particular heading, but not found in the section having that heading, may also be found elsewhere in this description. Embodiments are described herein according to the following outline:

1. General Overview

2. System Overview

3. Autonomous Vehicle Architecture

4. Autonomous Vehicle Inputs

5. Autonomous Vehicle Planning

6. Autonomous Vehicle Control

7. Autonomous Vehicle Route Modification

General Overview

Embodiments disclosed in this description provide improved vehicle location by, for example, maneuvering the vehicle into a different lane on a roadway to increase the amount of localization reference information available for determining the location of the vehicle. Some example embodiments include maneuvering the vehicle out of a lane that lacks sufficient lane markings to demarcate the lane into another lane where better lane markings are present. Other example embodiments include maneuvering the vehicle out of a lane where an obstruction hinders reception or detection of a GPS satellite signal into another lane where the signal is detectable.

System Overview

FIG. A1 shows an example of an autonomous vehicle A100 having autonomous capability.

As used herein, the term “autonomous capability” refers to a function, feature, or facility that enables a vehicle to be partially or fully operated without real-time human intervention, including without limitation fully autonomous vehicles, highly autonomous vehicles, and conditionally autonomous vehicles.

As used herein, an autonomous vehicle (AV) is a vehicle that possesses autonomous capability.

As used herein, “vehicle” includes means of transportation of goods or people. For example, cars, buses, trains, airplanes, drones, trucks, boats, ships, submersibles, dirigibles, etc. A driverless car is an example of a vehicle.

As used herein, “trajectory” refers to a path or route to navigate an AV from a first spatiotemporal location to second spatiotemporal location. In an embodiment, the first spatiotemporal location is referred to as the initial or starting location and the second spatiotemporal location is referred to as the destination, final location, goal, goal position, or goal location. In some examples, a trajectory is made up of one or more segments (e.g., sections of road) and each segment is made up of one or more blocks (e.g., portions of a lane or intersection). In an embodiment, the spatiotemporal locations correspond to real world locations. For example, the spatiotemporal locations are pick up or drop-off locations to pick up or drop-off persons or goods.

As used herein, “sensor(s)” includes one or more hardware components that detect information about the environment surrounding the sensor. Some of the hardware components can include sensing components (e.g., image sensors, biometric sensors), transmitting and/or receiving components (e.g., laser or radio frequency wave transmitters and receivers), electronic components such as analog-to-digital converters, a data storage device (such as a RAM and/or a nonvolatile storage), software or firmware components and data processing components such as an ASIC (application-specific integrated circuit), a microprocessor and/or a microcontroller.

As used herein, a “scene description” is a data structure (e.g., list) or data stream that includes one or more classified or labeled objects detected by one or more sensors on the AV vehicle or provided by a source external to the AV.

As used herein, a “road” is a physical area that can be traversed by a vehicle, and may correspond to a named thoroughfare (e.g., city street, interstate freeway, etc.) or may correspond to an unnamed thoroughfare.

As used herein, a “lane” is a portion of a road that can be traversed by a vehicle. A lane is sometimes identified based on lane markings. For example, a lane may correspond to most or all of the space between lane markings, or may correspond to only some (e.g., less than 50%) of the space between lane markings. For example, a road having lane markings spaced far apart might accommodate two or more vehicles between the markings, such that one vehicle can pass the other without traversing the lane markings, and thus could be interpreted as having a lane narrower than the space between the lane markings, or having two lanes between the lane markings. A lane could also be interpreted in the absence of lane markings. For example, a lane may be defined based on physical features of an environment, e.g., rocks and trees along a thoroughfare in a rural area. A lane could also be interpreted independent of lane markings or physical features. For example, a lane could be interpreted based on an arbitrary path free of obstructions in an area that otherwise lacks features that would be interpreted as lane boundaries. In an example scenario, an AV could interpret a lane through a wide (e.g., wide enough for two or more lanes) road that does not have lane markings. In this scenario, the AV could communicate information about the lane to other AVs so that the other AVs can use the same lane information to coordinate path planning among themselves.

The term “over-the-air (OTA) client” includes any AV, or any electronic device (e.g., computer, controller, IoT device, electronic control unit (ECU)) that is embedded in, coupled to, or in communication with an AV.

The term “over-the-air (OTA) update” means any update, change, deletion or addition to software, firmware, data or configuration settings, or any combination thereof, that is delivered to an OTA client using proprietary and/or standardized wireless communications technology, including but not limited to: cellular mobile communications (e.g., 2G, 3G, 4G, 5G), radio wireless area networks (e.g., WiFi) and/or satellite Internet.

The term “edge node” means one or more edge devices coupled to a network that provide a portal for communication with AVs and can communicate with other edge nodes and a cloud based computing platform, for scheduling and delivering OTA updates to OTA clients.

The term “edge device” means a device that implements an edge node and provides a physical wireless access point (AP) into enterprise or service provider (e.g., VERIZON, AT&T) core networks. Examples of edge devices include but are not limited to: computers, controllers, transmitters, routers, routing switches, integrated access devices (IADs), multiplexers, metropolitan area network (MAN) and wide area network (WAN) access devices.

“One or more” includes a function being performed by one element, a function being performed by more than one element, e.g., in a distributed fashion, several functions being performed by one element, several functions being performed by several elements, or any combination of the above.

It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the various described embodiments. The first contact and the second contact are both contacts, but they are not the same contact.

The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this description, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

As used herein, the term “if” is, optionally, construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context.

As used herein, an AV system refers to the AV along with the array of hardware, software, stored data, and data generated in real-time that supports the operation of the AV. In an embodiment, the AV system is incorporated within the AV. In an embodiment, the AV system is spread across several locations. For example, some of the software of the AV system is implemented on a cloud computing environment similar to cloud computing environment A300 described below with respect to FIG. A3.

In general, this document describes technologies applicable to any vehicles that have one or more autonomous capabilities including fully autonomous vehicles, highly autonomous vehicles, and conditionally autonomous vehicles, such as so-called Level 5, Level 4 and Level 3 vehicles, respectively (see SAE International's standard J3016: Taxonomy and Definitions for Terms Related to On-Road Motor Vehicle Automated Driving Systems, which is incorporated by reference in its entirety, for more details on the classification of levels of autonomy in vehicles). The technologies described in this document are also applicable to partially autonomous vehicles and driver assisted vehicles, such as so-called Level 2 and Level 1 vehicles (see SAE International's standard J3016: Taxonomy and Definitions for Terms Related to On-Road Motor Vehicle Automated Driving Systems). In an embodiment, one or more of the Level 1, 2, 3, 4 and 5 vehicle systems may automate certain vehicle operations (e.g., steering, braking, and using maps) under certain operating conditions based on processing of sensor inputs. The technologies described in this document can benefit vehicles in any levels, ranging from fully autonomous vehicles to human-operated vehicles.

Autonomous vehicles have advantages over vehicles that require a human driver. One advantage is safety. For example, in 2016, the United States experienced 6 million automobile accidents, 2.4 million injuries, 40,000 fatalities, and 13 million vehicles in crashes, estimated at a societal cost of $910+ billion. U.S. traffic fatalities per 100 million miles traveled have been reduced from about six to about one from 1965 to 2015, in part due to additional safety measures deployed in vehicles. For example, an additional half second of warning that a crash is about to occur is believed to mitigate 60% of front-to-rear crashes. However, passive safety features (e.g., seat belts, airbags) have likely reached their limit in improving this number. Thus, active safety measures, such as automated control of a vehicle, are the likely next step in improving these statistics. Because human drivers are believed to be responsible for a critical pre-crash event in 95% of crashes, automated driving systems are likely to achieve better safety outcomes, e.g., by reliably recognizing and avoiding critical situations better than humans; making better decisions, obeying traffic laws, and predicting future events better than humans; and reliably controlling a vehicle better than a human.

Referring to FIG. A1, an AV system A120 operates the AV A100 along a trajectory A198 through an environment A190 to a destination A199 (sometimes referred to as a final location) while avoiding objects (e.g., natural obstructions A191, vehicles A193, pedestrians A192, cyclists, and other obstacles) and obeying rules of the road (e.g., rules of operation or driving preferences).

In an embodiment, the AV system A120 includes devices A101 that are instrumented to receive and act on operational commands from the computer processors A146. In an embodiment, computing processors A146 are similar to the processor A304 described below in reference to FIG. A3. Examples of devices A101 include a steering control A102, brakes A103, gears, accelerator pedal or other acceleration control mechanisms, windshield wipers, side-door locks, window controls, and turn-indicators.

In an embodiment, the AV system A120 includes sensors A121 for measuring or inferring properties of state or condition of the AV A100, such as the AV's position, linear and angular velocity and acceleration, and heading (e.g., an orientation of the leading end of AV A100). Example of sensors A121 are GPS, inertial measurement units (IMU) that measure both vehicle linear accelerations and angular rates, wheel speed sensors for measuring or estimating wheel slip ratios, wheel brake pressure or braking torque sensors, engine torque or wheel torque sensors, and steering angle and angular rate sensors.

In an embodiment, the sensors A121 also include sensors for sensing or measuring properties of the AV's environment. For example, monocular or stereo video cameras A122 in the visible light, infrared or thermal (or both) spectra, LiDAR A123, RADAR, ultrasonic sensors, time-of-flight (TOF) depth sensors, speed sensors, temperature sensors, humidity sensors, and precipitation sensors.

In an embodiment, the AV system A120 includes a data storage unit A142 and memory A144 for storing machine instructions associated with computer processors A146 or data collected by sensors A121. In an embodiment, the data storage unit A142 is similar to the ROM A308 or storage device A310 described below in relation to FIG. A3. In an embodiment, memory A144 is similar to the main memory A306 described below. In an embodiment, the data storage unit A142 and memory A144 store historical, real-time, and/or predictive information about the environment A190. In an embodiment, the stored information includes maps, driving performance, traffic congestion updates or weather conditions. In an embodiment, data relating to the environment A190 is transmitted to the AV A100 via a communications channel from a remotely located database A134.

In an embodiment, the AV system A120 includes communications devices A140 for communicating measured or inferred properties of other vehicles' states and conditions, such as positions, linear and angular velocities, linear and angular accelerations, and linear and angular headings to the AV A100. These devices include Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communication devices and devices for wireless communications over point-to-point or ad hoc networks or both. In an embodiment, the communications devices A140 communicate across the electromagnetic spectrum (including radio and optical communications) or other media (e.g., air and acoustic media). A combination of Vehicle-to-Vehicle (V2V) Vehicle-to-Infrastructure (V2I) communication (and, in some embodiments, one or more other types of communication) is sometimes referred to as Vehicle-to-Everything (V2X) communication. V2X communication typically conforms to one or more communications standards for communication with, between, and among autonomous vehicles.

In an embodiment, the communication devices A140 include communication interfaces. For example, wired, wireless, WiMAX, Wi-Fi, Bluetooth, satellite, cellular, optical, near field, infrared, or radio interfaces. The communication interfaces transmit data from a remotely located database A134 to AV system A120. In an embodiment, the remotely located database A134 is embedded in a cloud computing environment A200 as described in FIG. A2. The communication interfaces A140 transmit data collected from sensors A121 or other data related to the operation of AV A100 to the remotely located database A134. In an embodiment, communication interfaces A140 transmit information that relates to teleoperations to the AV A100. In some embodiments, the AV A100 communicates with other remote (e.g., “cloud”) servers A136.

In an embodiment, the remotely located database A134 also stores and transmits digital data (e.g., storing data such as road and street locations). Such data is stored on the memory A144 on the AV A100, or transmitted to the AV A100 via a communications channel from the remotely located database A134.

In an embodiment, the remotely located database A134 stores and transmits historical information about driving properties (e.g., speed and acceleration profiles) of vehicles that have previously traveled along trajectory A198 at similar times of day. In one implementation, such data may be stored on the memory A144 on the AV A100, or transmitted to the AV A100 via a communications channel from the remotely located database A134.

Computing devices A146 located on the AV A100 algorithmically generate control actions based on both real-time sensor data and prior information, allowing the AV system A120 to execute its autonomous driving capabilities.

In an embodiment, the AV system A120 includes computer peripherals A132 coupled to computing devices A146 for providing information and alerts to, and receiving input from, a user (e.g., an occupant or a remote user) of the AV A100. In an embodiment, peripherals A132 are similar to the display A312, input device A314, and cursor controller A316 discussed below in reference to FIG. A3. The coupling is wireless or wired. Any two or more of the interface devices may be integrated into a single device.

FIG. A2 illustrates an example “cloud” computing environment. Cloud computing is a model of service delivery for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g. networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services). In typical cloud computing systems, one or more large cloud data centers house the machines used to deliver the services provided by the cloud. Referring now to FIG. A2, the cloud computing environment A200 includes cloud data centers A204 a, A204 b, and A204 c that are interconnected through the cloud A202. Data centers A204 a, A204 b, and A204 c provide cloud computing services to computer systems A206 a, A206 b, A206 c, A206 d, A206 e, and A206 f connected to cloud A202.

The cloud computing environment A200 includes one or more cloud data centers. In general, a cloud data center, for example the cloud data center A204 a shown in FIG. A2, refers to the physical arrangement of servers that make up a cloud, for example the cloud A202 shown in FIG. A2, or a particular portion of a cloud. For example, servers are physically arranged in the cloud datacenter into rooms, groups, rows, and racks. A cloud datacenter has one or more zones, which include one or more rooms of servers. Each room has one or more rows of servers, and each row includes one or more racks. Each rack includes one or more individual server nodes. In some implementation, servers in zones, rooms, racks, and/or rows are arranged into groups based on physical infrastructure requirements of the datacenter facility, which include power, energy, thermal, heat, and/or other requirements. In an embodiment, the server nodes are similar to the computer system described in FIG. A3. The data center A204 a has many computing systems distributed through many racks.

The cloud A202 includes cloud data centers A204 a, A204 b, and A204 c along with the network and networking resources (for example, networking equipment, nodes, routers, switches, and networking cables) that interconnect the cloud data centers A204 a, A204 b, and A204 c and help facilitate the computing systems' A206 a-f access to cloud computing services. In an embodiment, the network represents any combination of one or more local networks, wide area networks, or internetworks coupled using wired or wireless links deployed using terrestrial or satellite connections. Data exchanged over the network, is transferred using any number of network layer protocols, such as Internet Protocol (IP), Multiprotocol Label Switching (MPLS), Asynchronous Transfer Mode (ATM), Frame Relay, etc. Furthermore, in embodiments where the network represents a combination of multiple sub-networks, different network layer protocols are used at each of the underlying sub-networks. In some embodiments, the network represents one or more interconnected internetworks, such as the public Internet.

The computing systems A206 a-f or cloud computing services consumers are connected to the cloud A202 through network links and network adapters. In an embodiment, the computing systems A206 a-f are implemented as various computing devices, for example servers, desktops, laptops, tablet, smartphones, Internet of Things (IoT) devices, autonomous vehicles (including, cars, drones, shuttles, trains, buses, etc.) and consumer electronics. In an embodiment, the computing systems A206 a-f are implemented in or as a part of other systems.

FIG. A3 illustrates a computer system A300. In an implementation, the computer system A300 is a special purpose computing device. The special-purpose computing device is hard-wired to perform the techniques or includes digital electronic devices such as one or more application-specific integrated circuits (ASICs) or field programmable gate arrays (FPGAs) that are persistently programmed to perform the techniques, or may include one or more general purpose hardware processors programmed to perform the techniques pursuant to program instructions in firmware, memory, other storage, or a combination. Such special-purpose computing devices may also combine custom hard-wired logic, ASICs, or FPGAs with custom programming to accomplish the techniques. In various embodiments, the special-purpose computing devices are desktop computer systems, portable computer systems, handheld devices, network devices or any other device that incorporates hard-wired and/or program logic to implement the techniques.

In an embodiment, the computer system A300 includes a bus A302 or other communication mechanism for communicating information, and a hardware processor A304 coupled with a bus A302 for processing information. The hardware processor A304 is, for example, a general-purpose microprocessor. The computer system A300 also includes a main memory A306, such as a random-access memory (RAM) or other dynamic storage device, coupled to the bus A302 for storing information and instructions to be executed by processor A304. In one implementation, the main memory A306 is used for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor A304. Such instructions, when stored in non-transitory storage media accessible to the processor A304, render the computer system A300 into a special-purpose machine that is customized to perform the operations specified in the instructions.

In an embodiment, the computer system A300 further includes a read only memory (ROM) A308 or other static storage device coupled to the bus A302 for storing static information and instructions for the processor A304. A storage device A310, such as a magnetic disk, optical disk, solid-state drive, or three-dimensional cross point memory is provided and coupled to the bus A302 for storing information and instructions.

In an embodiment, the computer system A300 is coupled via the bus A302 to a display A312, such as a cathode ray tube (CRT), a liquid crystal display (LCD), plasma display, light emitting diode (LED) display, or an organic light emitting diode (OLED) display for displaying information to a computer user. An input device A314, including alphanumeric and other keys, is coupled to bus A302 for communicating information and command selections to the processor A304. Another type of user input device is a cursor controller A316, such as a mouse, a trackball, a touch-enabled display, or cursor direction keys for communicating direction information and command selections to the processor A304 and for controlling cursor movement on the display A312. This input device typically has two degrees of freedom in two axes, a first axis (e.g., x-axis) and a second axis (e.g., y-axis), that allows the device to specify positions in a plane.

According to one embodiment, the techniques herein are performed by the computer system A300 in response to the processor A304 executing one or more sequences of one or more instructions contained in the main memory A306. Such instructions are read into the main memory A306 from another storage medium, such as the storage device A310. Execution of the sequences of instructions contained in the main memory A306 causes the processor A304 to perform the process steps described herein. In alternative embodiments, hard-wired circuitry is used in place of or in combination with software instructions.

The term “storage media” as used herein refers to any non-transitory media that store data and/or instructions that cause a machine to operate in a specific fashion. Such storage media includes non-volatile media and/or volatile media. Non-volatile media includes, for example, optical disks, magnetic disks, solid-state drives, or three-dimensional cross point memory, such as the storage device A310. Volatile media includes dynamic memory, such as the main memory A306. Common forms of storage media include, for example, a floppy disk, a flexible disk, hard disk, solid-state drive, magnetic tape, or any other magnetic data storage medium, a CD-ROM, any other optical data storage medium, any physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, NV-RAM, or any other memory chip or cartridge.

Storage media is distinct from but may be used in conjunction with transmission media. Transmission media participates in transferring information between storage media. For example, transmission media includes coaxial cables, copper wire and fiber optics, including the wires that comprise the bus A302. Transmission media can also take the form of acoustic or light waves, such as those generated during radio-wave and infrared data communications.

In an embodiment, various forms of media are involved in carrying one or more sequences of one or more instructions to the processor A304 for execution. For example, the instructions are initially carried on a magnetic disk or solid-state drive of a remote computer. The remote computer loads the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to the computer system A300 receives the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector receives the data carried in the infrared signal and appropriate circuitry places the data on the bus A302. The bus A302 carries the data to the main memory A306, from which processor A304 retrieves and executes the instructions. The instructions received by the main memory A306 may optionally be stored on the storage device A310 either before or after execution by processor A304.

The computer system A300 also includes a communication interface A318 coupled to the bus A302. The communication interface A318 provides a two-way data communication coupling to a network link A320 that is connected to a local network A322. For example, the communication interface A318 is an integrated service digital network (ISDN) card, cable modem, satellite modem, or a modem to provide a data communication connection to a corresponding type of telephone line. As another example, the communication interface A318 is a local area network (LAN) card to provide a data communication connection to a compatible LAN. In some implementations, wireless links are also implemented. In any such implementation, the communication interface A318 sends and receives electrical, electromagnetic, or optical signals that carry digital data streams representing various types of information.

The network link A320 typically provides data communication through one or more networks to other data devices. For example, the network link A320 provides a connection through the local network A322 to a host computer A324 or to a cloud data center or equipment operated by an Internet Service Provider (ISP) A326. The ISP A326 in turn provides data communication services through the world-wide packet data communication network now commonly referred to as the “Internet” A328. The local network A322 and Internet A328 both use electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on the network link A320 and through the communication interface A318, which carry the digital data to and from the computer system A300, are example forms of transmission media. In an embodiment, the network A320 contains the cloud A202 or a part of the cloud A202 described above.

The computer system A300 sends messages and receives data, including program code, through the network(s), the network link A320, and the communication interface A318. In an embodiment, the computer system A300 receives code for processing. The received code is executed by the processor A304 as it is received, and/or stored in storage device A310, or other non-volatile storage for later execution.

Autonomous Vehicle Architecture

FIG. B1 shows an example architecture B100 for an autonomous vehicle (e.g., the AV A100 shown in FIG. Al). The architecture B100 includes a perception module B102 (sometimes referred to as a perception circuit), a planning module B104 (sometimes referred to as a planning circuit), a control module B106 (sometimes referred to as a control circuit), a localization module B108 (sometimes referred to as a localization circuit), and a database module B110 (sometimes referred to as a database circuit). Each module plays a role in the operation of the AV A100. Together, the modules B102, B104, B106, B108, and B110 may be part of the AV system A120 shown in FIG. A1. In some embodiments, any of the modules B102, B104, B106, B108, and B110 is a combination of computer software (e.g., executable code stored on a computer-readable medium) and computer hardware (e.g., one or more microprocessors, microcontrollers, application-specific integrated circuits [ASICs]), hardware memory devices, other types of integrated circuits, other types of computer hardware, or a combination of any or all of these things). Each of the modules B102, B104, B106, B108, and B110 is sometimes referred to as a processing circuit (e.g., computer hardware, computer software, or a combination of the two). A combination of any or all of the modules B102, B104, B106, B108, and B110 is also an example of a processing circuit.

In use, the planning module B104 receives data representing a destination B112 and determines data representing a trajectory B114 (sometimes referred to as a route) that can be traveled by the AV A100 to reach (e.g., arrive at) the destination B112. In order for the planning module B104 to determine the data representing the trajectory B114, the planning module B104 receives data from the perception module B102, the localization module B108, and the database module B110.

The perception module B102 identifies nearby physical objects using one or more sensors A121, e.g., as also shown in FIG. Al. The objects are classified (e.g., grouped into types such as pedestrian, bicycle, automobile, traffic sign, etc.) and a scene description including the classified objects B116 is provided to the planning module B104.

The planning module B104 also receives data representing the AV position B118 from the localization module B108. The localization module B108 determines the AV position by using data from the sensors A121 and data from the database module B110 (e.g., a geographic data) to calculate a position. For example, the localization module B108 uses data from a GNSS (Global Navigation Satellite System) sensor and geographic data to calculate a longitude and latitude of the AV. In an embodiment, data used by the localization module B108 includes high-precision maps of the roadway geometric properties, maps describing road network connectivity properties, maps describing roadway physical properties (such as traffic speed, traffic volume, the number of vehicular and cyclist traffic lanes, lane width, lane traffic directions, or lane marker types and locations, or combinations of them), and maps describing the spatial locations of road features such as crosswalks, traffic signs or other travel signals of various types. In an embodiment, the high-precision maps are constructed by adding data through automatic or manual annotation to low-precision maps.

The control module B106 receives the data representing the trajectory B114 and the data representing the AV position B118 and operates the control functions B120 a-c (e.g., steering, throttling, braking, ignition) of the AV in a manner that will cause the AV A100 to travel the trajectory B114 to the destination B112. For example, if the trajectory B114 includes a left turn, the control module B106 will operate the control functions B120 a-c in a manner such that the steering angle of the steering function will cause the AV A100 to turn left and the throttling and braking will cause the AV A100 to pause and wait for passing pedestrians or vehicles before the turn is made.

Autonomous Vehicle Inputs

FIG. C1 shows an example of inputs C102 a-d (e.g., sensors A121 shown in FIG. A1) and outputs C104 a-d (e.g., sensor data) that is used by the perception module B102 (FIG. B1). One input C102 a is a LiDAR (Light Detection and Ranging) system (e.g., LiDAR A123 shown in FIG. Al). LiDAR is a technology that uses light (e.g., bursts of light such as infrared light) to obtain data about physical objects in its line of sight. A LiDAR system produces LiDAR data as output C104 a. For example, LiDAR data is collections of 3D or 2D points (also known as a point clouds) that are used to construct a representation of the environment A190.

Another input C102 b is a RADAR system. RADAR is a technology that uses radio waves to obtain data about nearby physical objects. RADARs can obtain data about objects not within the line of sight of a LiDAR system. A RADAR system C102b produces RADAR data as output C104 b. For example, RADAR data are one or more radio frequency electromagnetic signals that are used to construct a representation of the environment A190.

Another input C102 c is a camera system. A camera system uses one or more cameras (e.g., digital cameras using a light sensor such as a charge-coupled device [CCD]) to obtain information about nearby physical objects. A camera system produces camera data as output C104c. Camera data often takes the form of image data (e.g., data in an image data format such as RAW, JPEG, PNG, etc.). In some examples, the camera system has multiple independent cameras, e.g., for the purpose of stereopsis (stereo vision), which enables the camera system to perceive depth. Although the objects perceived by the camera system are described here as “nearby,” this is relative to the AV. In use, the camera system may be configured to “see” objects far, e.g., up to a kilometer or more ahead of the AV. Accordingly, the camera system may have features such as sensors and lenses that are optimized for perceiving objects that are far away.

Another input C102 d is a traffic light detection (TLD) system. A TLD system uses one or more cameras to obtain information about traffic lights, street signs, and other physical objects that provide visual navigation information. A TLD system produces TLD data as output C104 d. TLD data often takes the form of image data (e.g., data in an image data format such as RAW, JPEG, PNG, etc.). A TLD system differs from a system incorporating a camera in that a TLD system uses a camera with a wide field of view (e.g., using a wide-angle lens or a fish-eye lens) in order to obtain information about as many physical objects providing visual navigation information as possible, so that the AV A100 has access to all relevant navigation information provided by these objects. For example, the viewing angle of the TLD system may be about 120 degrees or more.

In some embodiments, outputs C104 a-d are combined using a sensor fusion technique. Thus, either the individual outputs C104 a-d are provided to other systems of the AV A100 (e.g., provided to a planning module B104 as shown in FIG. B1), or the combined output can be provided to the other systems, either in the form of a single combined output or multiple combined outputs of the same type (e.g., using the same combination technique or combining the same outputs or both) or different types type (e.g., using different respective combination techniques or combining different respective outputs or both). In some embodiments, an early fusion technique is used. An early fusion technique is characterized by combining outputs before one or more data processing steps are applied to the combined output. In some embodiments, a late fusion technique is used. A late fusion technique is characterized by combining outputs after one or more data processing steps are applied to the individual outputs.

FIG. C2 shows an example of a LiDAR system C202 (e.g., the input C102 a shown in FIG. C1). The LiDAR system C202 emits light C204a-c from a light emitter C206 (e.g., a laser transmitter). Light emitted by a LiDAR system is typically not in the visible spectrum; for example, infrared light is often used. Some of the light C204b emitted encounters a physical object C208 (e.g., a vehicle) and reflects back to the LiDAR system C202. (Light emitted from a LiDAR system typically does not penetrate physical objects, e.g., physical objects in solid form.) The LiDAR system C202 also has one or more light detectors C210, which detect the reflected light. In an embodiment, one or more data processing systems associated with the LiDAR system generates an image C212 representing the field of view C214 of the LiDAR system. The image C212 includes information that represents the boundaries C216 of a physical object C208. In this way, the image C212 is used to determine the boundaries C216 of one or more physical objects near an AV.

FIG. C3 shows the LiDAR system C202 in operation. In the scenario shown in this figure, the AV A100 receives both camera system output C104c in the form of an image C302 and LiDAR system output C104 a in the form of LiDAR data points C304. In use, the data processing systems of the AV A100 compares the image C302 to the data points C304. In particular, a physical object C306 identified in the image C302 is also identified among the data points C304. In this way, the AV A100 perceives the boundaries of the physical object based on the contour and density of the data points C304.

FIG. C4 shows the operation of the LiDAR system C202 in additional detail. As described above, the AV A100 detects the boundary of a physical object based on characteristics of the data points detected by the LiDAR system C202. As shown in FIG. C4, a flat object, such as the ground C402, will reflect light C404 a-d emitted from a LiDAR system C202 in a consistent manner. Put another way, because the LiDAR system C202 emits light using consistent spacing, the ground C402 will reflect light back to the LiDAR system C202 with the same consistent spacing. As the AV A100 travels over the ground C402, the LiDAR system C202 will continue to detect light reflected by the next valid ground point C406 if nothing is obstructing the road. However, if an object C408 obstructs the road, light C404 e-f emitted by the LiDAR system C202 will be reflected from points C410 a-b in a manner inconsistent with the expected consistent manner. From this information, the AV A100 can determine that the object C408 is present.

Path Planning

FIG. D1 shows a block diagram D100 of the relationships between inputs and outputs of a planning module B104 (e.g., as shown in FIG. B1). In general, the output of a planning module B104 is a route D102 from a start point D104 (e.g., source location or initial location), and an end point D106 (e.g., destination or final location). The route D102 is typically defined by one or more segments. For example, a segment is a distance to be traveled over at least a portion of a street, road, highway, driveway, or other physical area appropriate for automobile travel. In some examples, e.g., if the AV A100 is an off-road capable vehicle such as a four-wheel-drive (4WD) or all-wheel-drive (AWD) car, SUV, pick-up truck, or the like, the route D102 includes “off-road” segments such as unpaved paths or open fields.

In addition to the route D102, a planning module also outputs lane-level route planning data D108. The lane-level route planning data D108 is used to traverse segments of the route D102 based on conditions of the segment at a particular time. For example, if the route D102 includes a multi-lane highway, the lane-level route planning data D108 includes trajectory planning data D110 that the AV A100 can use to choose a lane among the multiple lanes, e.g., based on whether an exit is approaching, whether one or more of the lanes have other vehicles, or other factors that vary over the course of a few minutes or less. Similarly, in some implementations, the lane-level route planning data D108 includes speed constraints D112 specific to a segment of the route D102. For example, if the segment includes pedestrians or un-expected traffic, the speed constraints D112 may limit the AV A100 to a travel speed slower than an expected speed, e.g., a speed based on speed limit data for the segment.

In an embodiment, the inputs to the planning module B104 includes database data D114 (e.g., from the database module B110 shown in FIG. B1), current location data D116 (e.g., the AV position B118 shown in FIG. B1), destination data D118 (e.g., for the destination B112 shown in FIG. B1), and object data D120 (e.g., the classified objects B116 as perceived by the perception module B102 as shown in FIG. B1). In some embodiments, the database data D114 includes rules used in planning. Rules are specified using a formal language, e.g., using Boolean logic. In any given situation encountered by the AV A100, at least some of the rules will apply to the situation. A rule applies to a given situation if the rule has conditions that are met based on information available to the AV A100, e.g., information about the surrounding environment. Rules can have priority. For example, a rule that says, “if the road is a freeway, move to the leftmost lane” can have a lower priority than “if the exit is approaching within a mile, move to the rightmost lane.”

FIG. D2 shows a directed graph D200 used in path planning, e.g., by the planning module B104 (FIG. B1). In general, a directed graph D200 like the one shown in FIG. D2 is used to determine a path between any start point D202 and end point D204. In real-world terms, the distance separating the start point D202 and end point D204 may be relatively large (e.g, in two different metropolitan areas) or may be relatively small (e.g., two intersections abutting a city block or two lanes of a multi-lane road).

In an embodiment, the directed graph D200 has nodes D206 a-d representing different locations between the start point D202 and the end point D204 that could be occupied by an AV A100. In some examples, e.g., when the start point D202 and end point D204 represent different metropolitan areas, the nodes D206 a-d represent segments of roads. In some examples, e.g., when the start point D202 and the end point D204 represent different locations on the same road, the nodes D206 a-d represent different positions on that road. In this way, the directed graph D200 includes information at varying levels of granularity. In an embodiment, a directed graph having high granularity is also a subgraph of another directed graph having a larger scale. For example, a directed graph in which the start point D202 and the end point D204 are far away (e.g., many miles apart) has most of its information at a low granularity and is based on stored data, but also includes some high granularity information for the portion of the graph that represents physical locations in the field of view of the AV A100.

The nodes D206 a-d are distinct from objects D208 a-b which cannot overlap with a node. In an embodiment, when granularity is low, the objects D208 a-b represent regions that cannot be traversed by automobile, e.g., areas that have no streets or roads. When granularity is high, the objects D208 a-b represent physical objects in the field of view of the AV A100, e.g., other automobiles, pedestrians, or other entities with which the AV A100 cannot share physical space. In an embodiment, some or all of the objects D208 a-b are a static objects (e.g., an object that does not change position such as a street lamp or utility pole) or dynamic objects (e.g., an object that is capable of changing position such as a pedestrian or other car).

The nodes D206 a-d are connected by edges D210 a-c. If two nodes D206 a-b are connected by an edge D210 a, it is possible for an AV A100 to travel between one node D206 a and the other node D206 b, e.g., without having to travel to an intermediate node before arriving at the other node D206 b. (When we refer to an AV A100 traveling between nodes, we mean that the AV A100 travels between the two physical positions represented by the respective nodes.) The edges D210 a-c are often bidirectional, in the sense that an AV A100 travels from a first node to a second node, or from the second node to the first node. In an embodiment, edges D210 a-c are unidirectional, in the sense that an AV A100 can travel from a first node to a second node, however the AV A100 cannot travel from the second node to the first node. Edges D210 a-c are unidirectional when they represent, for example, one-way streets, individual lanes of a street, road, or highway, or other features that can only be traversed in one direction due to legal or physical constraints.

In an embodiment, the planning module B104 uses the directed graph D200 to identify a path D212 made up of nodes and edges between the start point D202 and end point D204.

An edge D210 a-c has an associated cost D214 a-b. The cost D214 a-b is a value that represents the resources that will be expended if the AV A100 chooses that edge. A typical resource is time. For example, if one edge D210 a represents a physical distance that is twice that as another edge D210 b, then the associated cost D214 a of the first edge D210 a may be twice the associated cost D214 b of the second edge D210 b. Other factors that affect time include expected traffic, number of intersections, speed limit, etc. Another typical resource is fuel economy. Two edges D210 a-b may represent the same physical distance, but one edge D210 a may require more fuel than another edge D210 b, e.g., because of road conditions, expected weather, etc.

When the planning module B104 identifies a path D212 between the start point D202 and end point D204, the planning module B104 typically chooses a path optimized for cost, e.g., the path that has the least total cost when the individual costs of the edges are added together.

Autonomous Vehicle Control

FIG. E1 shows a block diagram E100 of the inputs and outputs of a control module B106 (e.g., as shown in FIG. B1). A control module operates in accordance with a controller E102 which includes, for example, one or more processors (e.g., one or more computer processors such as microprocessors or microcontrollers or both) similar to processor A304, short-term and/or long-term data storage (e.g., memory random-access memory or flash memory or both) similar to main memory A306, ROM A308, and storage device A310, and instructions stored in memory that carry out operations of the controller E102 when the instructions are executed (e.g., by the one or more processors).

In an embodiment, the controller E102 receives data representing a desired output E104. The desired output E104 typically includes a velocity, e.g., a speed and a heading. The desired output E104 can be based on, for example, data received from a planning module B104 (e.g., as shown in FIG. B1). In accordance with the desired output E104, the controller E102 produces data usable as a throttle input E106 and a steering input E108. The throttle input E106 represents the magnitude in which to engage the throttle (e.g., acceleration control) of an AV A100, e.g., by engaging the steering pedal, or engaging another throttle control, to achieve the desired output E104. In some examples, the throttle input E106 also includes data usable to engage the brake (e.g., deceleration control) of the AV A100. The steering input E108 represents a steering angle, e.g., the angle at which the steering control (e.g., steering wheel, steering angle actuator, or other functionality for controlling steering angle) of the AV should be positioned to achieve the desired output E104.

In an embodiment, the controller E102 receives feedback that is used in adjusting the inputs provided to the throttle and steering. For example, if the AV A100 encounters a disturbance E110, such as a hill, the measured speed E112 of the AV A100 is lowered below the desired output speed. In an embodiment, any measured output E114 is provided to the controller E102 so that the necessary adjustments are performed, e.g., based on the differential E113 between the measured speed and desired output. The measured output E114 includes measured position E116, measured velocity E118, (including speed and heading), measured acceleration E120, and other outputs measurable by sensors of the AV A100.

In an embodiment, information about the disturbance E110 is detected in advance, e.g., by a sensor such as a camera or LiDAR sensor, and provided to a predictive feedback module E122. The predictive feedback module E122 then provides information to the controller E102 that the controller E102 can use to adjust accordingly. For example, if the sensors of the AV A100 detect (“see”) a hill, this information can be used by the controller E102 to prepare to engage the throttle at the appropriate time to avoid significant deceleration.

FIG. E2 shows a block diagram E200 of the inputs, outputs, and components of the controller E102. The controller E102 has a speed profiler E202 which affects the operation of a throttle/brake controller E204. For example, the speed profiler E202 instructs the throttle/brake controller E204 to engage acceleration or engage deceleration using the throttle/brake E206 depending on, e.g., feedback received by the controller E102 and processed by the speed profiler E202.

The controller E102 also has a lateral tracking controller E208 which affects the operation of a steering controller E210. For example, the lateral tracking controller E208 instructs the steering controller E210 to adjust the position of the steering angle actuator E212 depending on, e.g., feedback received by the controller E102 and processed by the lateral tracking controller E208.

The controller E102 receives several inputs used to determine how to control the throttle/brake E206 and steering angle actuator E212. A planning module B104 provides information used by the controller E102, for example, to choose a heading when the AV A100 begins operation and to determine which road segment to traverse when the AV A100 reaches an intersection. A localization module B108 provides information to the controller E102 describing the current location of the AV A100, for example, so that the controller E102 can determine if the AV A100 is at a location expected based on the manner in which the throttle/brake E206 and steering angle actuator E212 are being controlled. In an embodiment, the controller E102 receives information from other inputs E214, e.g., information received from databases, computer networks, etc.

Autonomous Vehicle Route Modification

One aspect of controlling the AV A100 includes automatically determining the location of the AV A100. Different driving scenarios may limit the availability of localization reference information, such as global navigation satellite system (GNSS) satellite signals or lane markings on a roadway. Controlling the AV A100 includes modifying the vehicle route by maneuvering the AV A100 in a way that increases the availability or detectability of such localization reference information, which increases the precision of the location determination.

A processor, such as the processor A146 or A304 mentioned above, uses at least one indication from at least one sensor, such as the sensor A121 mentioned above, to make the location determination and to maneuver the AV A100 if necessary or desired. The processor A146 will be included for discussion purposes but the processor A304 or a combination of such processors may be used in some embodiments. A single sensor A121 will be used for discussion purposes but more than one such sensor may be used in some embodiments. The sensor A121 is configured to detect the type of localization reference information used in a given scenario.

FIG. F1 is a flowchart diagram F100 that summarizes an example method of controlling the AV A100 including modifying how the AV A100 is traveling along a route to provide improved vehicle location information. At F102, the processor A146 determines a location of the AV A100 with a first precision based on at least one localization reference while the AV A100 is traveling in a first lane of a roadway. At F104, the processor A146 determines that at least one characteristic of the first precision is below a threshold. In embodiments in which the characteristic of interest is the precision, itself, the threshold may correspond to a level of certainty provided by the determined location. In embodiments in which the characteristic of interest corresponds to an amount of localization reference information used for determining the location, the threshold may correspond to a number of sources of such information. Given this description, those skilled in the art will be able to select an appropriate characteristic of the precision of a determined location and a corresponding threshold to meet the needs of their particular implementation.

At F106, the processor A146 maneuvers the AV A100 to a second lane of the roadway based on the characteristic of the first precision being below the threshold. Maneuvering the AV A100 into the second lane allows the processor A146 to determine the location of the vehicle with a second precision while the AV A100 is traveling in the second lane. The second precision is above the threshold because of increased or improved availability of localization reference information while the vehicle is in the second lane compared to that which was available while the vehicle travels in the first lane.

The processor A146 obtains information regarding at least one localization reference from at least one of the sensors A121 that is configured to provide such information. For example, when the localization reference comprises lane markings sufficient to demarcate a lane on a roadway, the sensor A121 comprises a LIDAR sensor or vision system that is capable of detecting lane markings. In embodiments where the localization reference comprises a GNSS satellite signal, the sensor A121 is configured to detect such signals and the sensor A121, the processor A146, or both are configured to determine the location of the AV A100 based on such signals.

FIG. F2 schematically illustrates an example scenario in which the processor A146 maneuvers the AV A100 to increase the amount of localization reference information useable for determining the vehicle location. In FIG. F2, the AV A100 is traveling along a roadway F110 in a first lane F112. Lane markings F114 and F116 demarcate or establish the boundaries or borders along the sides of the lane F112. A segment or portion F118 of the roadway F110 does not contain sufficient lane markings to demarcate the lane F112 to provide a desired precision when locating the AV A100 based upon the lane markings. In particular, the segment F118 does not have any of the lane markings F114.

The processor A146 utilizes information regarding the lane markings to control the vehicle steering and speed, for example, to stay centered in the lane while traveling along a route to a destination. When traveling along the segment F118, the processor A146 will not have sufficient lane marking information from the sensor A121 to make an accurate or precise location determination. In other words, when relying upon lane marking indications from the sensor A121 while traveling along the segment F118 in the first lane F112, the determined location of the AV A100 will have a first precision that is below a threshold corresponding to a desired level of precision. In this example, the characteristic of the precision and the threshold correspond to whether lane markings are present to sufficiently demarcate the lane. Since the lane markings F114 are not present along the segment F118, the precision of a location determination while the vehicle A100 is traveling in the lane F112 based on lane markings as the localization reference will not satisfy the first threshold. Under that circumstance, the processor A146 maneuvers the AV A100 into a second, different lane of the roadway F110.

As shown in FIG. F2, the processor A146 maneuvers the AVA 100 into a second lane F120 as shown at A100′. The lane F120 includes lane markings F122 and F124 on both sides of that lane along the illustrated portion of the roadway F110 including the segment F118. The processor A146, therefore, can make a location determination with a second precision, which is higher than the first precision and the example characteristic of the second precision will be above the threshold. Since the amount of localization reference information that the first precision was based on while the vehicle A100 was traveling in the first lane F112 is less than the amount of localization reference information provided by the lane markings F122 and F124 in the second lane F120, maneuvering the AV A100 into the second lane F120 provides an improved vehicle location determination. In this example scenario, more localization reference information corresponds to an increased precision of the location determination.

FIG. F3 illustrates another example scenario in which the processor A146 utilizes lane marking information for determining the location of the AV A100 at least for purposes of maintaining an appropriate position within the lane. In FIG. F3, the AV A100 is traveling along a roadway F130 that includes a bend or curve. Having sufficient lane marking information while the AV A100 is traveling along a curve in a roadway ensures that the AV A100 can properly navigate the roadway F130. The AV A100 is shown currently traveling in a first lane F132 that includes lane markings F134 and F136. A segment of the roadway F130 shown at F138 does not include lane markings to sufficiently demarcate the first lane F132.

The sensor A121 has a field of vision schematically shown at F140. The sensor A121 provides an indication to the processor A146 regarding the presence of lane markings within the field of vision F140. The processor A146 determines that there are insufficient lane markings along the segment F138 to determine the vehicle location along that segment with a desired level of precision. In some instances, the processor A146 makes such a determination based upon at least one location determination regarding the AV A100 on the segment F138.

The processor A146 maneuvers the AV A100 into a second, different lane of the roadway F130 to achieve a location determination having a second precision that is better compared to the precision available in the lane F132. In the scenario shown in FIG. F3, a lane F142 has lane markings F146 and the lane markings F134. Since the lane markings F134 are not present along the segment F138, the processor A146 determines that another lane F144 having lane markings F146 and F148 would be a better choice for traveling around the illustrated curve and along the segment F138. Accordingly, the processor A146 maneuvers the AV A100 into the lane F144 as show at A100′ at least for traveling along the curve shown in FIG. F3.

FIG. F4 shows another example scenario in which lane marking information is relied upon for determining the location of the AV A100. A roadway F150 includes a segment where the AV A100 passes underneath a structure F152, such as a bridge or overpass. Having sufficient lane marking information along that segment of the roadway F150 may be necessary when the processor A146 otherwise relies upon GNSS satellite information to determine the location of the AV A100. Underneath the structure F152, such signals may not be available and the processor A146 relies upon lane marking information to maintain accurate vehicle location information.

The roadway F150 includes lane markings F154 and F156 that demarcate the sides or edges of a lane F158. The lane markings F154 and F156 are not present underneath the structure F152. Another lane F160 is demarcated by lane markings F164 and F154. At least the lane marking F164 is available underneath the structure F152. Similarly, a lane marking F166 is available along the entire illustrated portion of the roadway F150 along one side of a lane F168. Under such a scenario, the processor A146 determines that there is more lane marking information available in the lanes F160 and F168 compared to the lane F158. Therefore, the processor A146 maneuvers the AV A100 as shown at A100′ into the lane F168 for purposes of traveling beneath the structure F152. Even though lane markings are not available on both sides of the lane F168, there is at least one lane marking available, which provides improved precision over that which would be available while traveling in the lane F158.

In the scenarios shown in FIGS. F2-F4, the localization reference information includes at least lane marking information that demarcates the lanes on a roadway. In such situations, the processor A146 is configured to select a second or different lane and maneuver the AV A100 into such a lane based on information regarding at least one other localization reference that is detectable by the sensor A121 while the AV A100 is in such a second lane but not in the first lane. The information used by the processor A146 for selecting a lane under such circumstances includes at least one of an output from the sensor A121 corresponding to detecting lane markings of the second lane, predetermined map information regarding lane markings in a vicinity of the AV A100, and stored information regarding the lane markings from at least one previous trip along the roadway. Some example embodiments include the processor A146 using a combination of such information.

For example, as the AV A100 travels along the roadway, the sensor A121 provides the processor A146 an indication regarding the presence or absence of lane markings within the field of view 140 on an ongoing basis. The processor A146 dynamically responds to the sensor indication and maneuvers the AV A100 into different lanes as may be useful under the particular circumstances.

Predetermined map information, which includes locations where particular segments of lanes do not have sufficient lane markings, may be available from a variety of sources. The processor A146 in some embodiments has access to such information either stored in memory on the AV A100 or through a subscription, for example, to an external database or service that is accessible using wireless communication techniques. The processor A146 in such embodiments essentially keeps track of the map information regarding the vicinity of the AV A100 location and uses that to determine where a lane change will provide more or better lane marking information.

The processor A146 is configured in some embodiments to store information regarding lane markings during at least one trip along a roadway including locations where the sensor A121 indicates that lane markings are insufficient to demarcate a lane, for example. The processor A146 in some embodiments also stores information regarding locations where a lane change resulted in increasing the precision of a location determination. During a subsequent trip along the same roadway, the processor A146 uses the previously stored data and current vehicle location information to maneuver the AV A100 among lanes on the roadway to avoid traveling along a segment of a lane where the lane markings are unavailable or insufficient for adequately demarcating the lane.

In some situations, the first lane of the roadway that does not have lane markings sufficient to demarcate that lane along a segment of a route that the AV A100 is following is a preferred lane for overall route planning purposes. The processor A146 is configured to determine when to maneuver the AV A100 back into the first lane from the second lane once sufficient lane markings are available to demarcate the first lane. This occurs, for example, after travelling past a segment of the roadway on which the first lane does not have adequate lane markings. The processor A146 determines if lane markings are detectable by the sensor A121 in a nearby segment of the first lane while the AV A100 is traveling in the second lane. The processor A146 maneuvers the AV A100 from the second lane into the first lane when such lane markings are available in the nearby segment of the first lane.

The processor A146 may determine when lane markings are detectable by the sensor A121 in the first lane based on indications from the sensor A121 regarding the ability of the sensor A121 to currently detect such lane markings. In some situations, the processor A146 uses predetermined map information or information stored from a previous trip along that roadway to make such a determination. The processor A146 is therefore capable of causing the AV A100 to follow a preplanned, preferred route and maintain a desired level of precision for location determinations along that route by maneuvering the AV A100 into different lanes as may be needed along the preplanned route.

The processor A146, in some embodiments, utilizes GNSS satellite information as the localization reference information. When the localization reference comprises GNSS satellite signals, the characteristic of interest of the precision with which a location determination is made or can be made corresponds to a number of GNSS satellite signals available or detectable by one or more sensors A121 onboard the AV A100. The threshold corresponds to, for example, a desired minimum number of satellite signals simultaneously detectable by the sensor A121. The processor A146 maneuvers the AV A100 into a lane along a current segment of a roadway to increase the availability of satellite signals for purposes of making location determinations when the currently detected number of satellite signals is below the threshold.

As schematically shown in FIG. F5, a low horizon GNSS satellite F170 may be outside of the look angle or detection angle of the sensor A121 on the AV A100 depending on the location of the AV A100. Obstructions F172 and F174 nearby a roadway F176 may prevent the sensor A121 from detecting a signal from the satellite F170 depending on the lane in which the AV A100 is traveling. Possible lane positions are schematically shown at F178, F180, and F182. When the AV A100 is traveling along a lane F178, the obstruction F172 blocks the satellite signal from the GNSS satellite F170. The obstruction F172 may be a building, for example, or a portion of the landscape such as trees, along the roadway F176. The obstruction F174 is further from the roadway F176 but is larger and, therefore, may still impede satellite signal reception when the AV A100 is in certain positions along the roadway F176.

As schematically shown in FIG. F5, when the AV A100 is traveling in a lane at F180 or F182, neither obstruction F172 or F174 will prevent the sensor A121 from having a clear line of sight or look angle for detecting a signal from the GNSS satellite F170. The processor A146, therefore, maneuvers the AV A100 out of the lane F178 and into one of the lanes F180 or F182 when traveling along a segment of the roadway F176 where the obstructions F172 or F174 may impede the sensor A121 from detecting a satellite signal.

FIG. F6 illustrates an example scenario in which the AV A100 is traveling along a roadway F190 in a lane F192. Several obstructions F194, F196, and F198 are situated nearby the roadway F190 close to the lane F192. When the AV A100 is traveling along the lane F192, one or more of those obstructions may impede the ability of the sensor A121 to receive a signal from a GNSS satellite. The processor A146 determines the location of the AV A100 based on a number of GNSS satellite signals that are detectable by the sensor A121. That determination has a first precision based on a first number of such signals that can be detected by the sensor A121. The processor A146 maneuvers the AV A100 into a second, different lane F200 as shown at A100′, based on the first precision being below the corresponding threshold, to increase the number of GNSS satellite signals detectable by the sensor A121. When a second, larger number of such signals are detectable by the sensor A121, the AV A100 location determination can be made with a second, higher precision compared to a first precision based on the first number of available satellite signals.

The processor A146 selects the lane to maneuver the AV A100 into by determining a position or location of an obstruction and selecting a lane further from that obstruction to reduce the likelihood that the obstruction will interfere with satellite signal reception by the sensor A121. In some embodiments, the processor A146 makes this determination based on information from the sensor A121. In such embodiments, the sensor A121 is capable of detecting the position of an obstruction relative to the AV A100. For example, the sensor A121 may include RADAR, LiDAR, or ultrasound sensing technologies for detecting an obstruction in or nearby the roadway. The processor A146 determines a position of the obstruction relative to the vehicle and selects a lane based on that determined position. The processor A146 selects a second lane to increase a distance between the AV A100 and the obstruction. By doing so, the processor A146 increases a number of GNSS satellites detectable by the sensor A121 from a first number while the AV A100 is traveling in the first lane to a second, larger number while the AV A100 is traveling in the second lane.

Other types of data that may be used by the processor A146 for identifying or locating obstructions and selecting a second lane includes data stored by the processor A146 during previous trips along a roadway and predetermined map data that provides indications of locations of obstructions relative to one or more lanes of a roadway.

In some embodiments, the processor A146 selects a second lane for increasing the number of satellite signals available to the sensor A121 based upon ephemeris data regarding positions of GNSS satellites. Such data is available and may be provided to the processor A146 through a subscription service, for example.

FIG. F7 schematically illustrates another scenario in which GNSS satellite information may be limited based upon at least one obstruction while AV A100 is traveling in a lane F210 on a roadway F212. A first vehicle F214 is in a lane F215 and a second vehicle F216 is in another lane F218. Those vehicles F214 and F216 will obstruct the ability of the sensor A121 to detect low horizon GNSS satellite signals when the AV A100 is situated between them and they are respectively on opposite sides of the AV A100. The processor A146 is configured to alter the manner in which the AV A100 is traveling along the roadway by changing a speed with which the AV A100 travels to avoid being situated between the vehicles F214 and F216.

For example, the processor A146 may determine that the AV A100 is situated between the vehicles F214 and F216 based upon information from the sensor A121 that detects the presence of such vehicles along the roadway F212. At the same time, the processor A146 recognizes that the number of satellite signals available to or detectable by the sensor A121 is below a desired number. The processor A146 alters a speed of the AV A100 to change the position of the AV A100 relative to or one or both of the obstructing vehicles F214 and F216 until those vehicles no longer prevent the sensor A121 from detecting GNSS satellite signals.

When the AV A100 is in either of the positions shown in FIG. F7, the vehicles F214 and F216 do not interfere with GNSS satellite signal reception. Once in such a position, the processor A146 readjusts the speed of the AV A100 as may be needed to continue travelling along the lane F210 at a preferred speed, which may be based on a posted speed limit of the roadway F212 or maintaining a selected distance from the vehicles F214 and F216.

The processor A146 is configured in this example embodiment to determine when the obstructing vehicles F214 and F216 are on opposite sides of the AV A100 and that maneuvering the AV A100 into an adjacent lane on the roadway F212 is not possible. Under those circumstances, the processor A146 does not attempt a maneuver as described previously but, instead, accelerates or decelerates the AV A100 while staying in the lane F210. This is another example way in which the processor A146 controls movement of the AV A100 to ensure that adequate localization reference information is available for making a location determination at a desired precision level.

The techniques and system features used in the example scenarios discussed above are combined in some embodiments, such as determining the vehicle location based on a combination of GNSS satellite and lane marking information. The disclosed features and techniques may be combined in various ways to realize a variety of embodiments. [000140] Although GNSS satellite signal and lane markings are used as localization references in the example embodiments described above, those embodiments and others are not necessarily limited to such information. For example, other embodiments include other types of localization references, such as localization objects or buildings that have sufficiently detectable features to allow using an iterative closest point algorithm to determine position information.

In the foregoing description, embodiments of the invention have been described with reference to numerous specific details that may vary from implementation to implementation. The description and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. The sole and exclusive indicator of the scope of the invention, and what is intended by the applicant to be the scope of the invention, is the literal and equivalent scope of the set of claims that issue from this application, in the specific form in which such claims issue, including any subsequent correction. Any definitions expressly set forth herein for terms contained in such claims shall govern the meaning of such terms as used in the claims. In addition, when we use the term “further comprising,” in the foregoing description or following claims, what follows this phrase can be an additional step or entity, or a sub-step/sub-entity of a previously-recited step or entity. 

We claim:
 1. A system for controlling a vehicle, the system comprising: at least one sensor configured to detect at least one localization reference; and at least one processor configured to determine a location of the vehicle with a first precision based on an indication from the at least one sensor while the vehicle is traveling in a first lane of a roadway; determine that at least one characteristic of the first precision is below a threshold; and based on the at least one characteristic being below the threshold, maneuver the vehicle to a second lane of the roadway.
 2. The system of claim 1, wherein the at least one processor is configured to determine the location of the vehicle with a second precision based on an indication from the at least one sensor while the vehicle is traveling in the second lane; and the at least one characteristic of the second precision is above the threshold.
 3. The system of claim 1, wherein the at least one localization reference comprises lane markings sufficient to demarcate the first lane and the at least one characteristic corresponds to a presence of the lane markings; or the at least one localization reference comprises a GPS satellite signal and the at least one characteristic corresponds to a number of GPS satellite signals.
 4. The system of claim 1, wherein the at least one processor is configured to select the second lane based on information regarding at least one other localization reference that is detectable by at the least one sensor while the vehicle is in the second lane but not in the first lane.
 5. The system of claim 4, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane; and the information comprises at least one of an output from the at least one sensor corresponding to detecting the lane markings of the second lane, predetermined map information regarding lane markings in a vicinity of the determined location of the vehicle, and predetermined information regarding the lane markings of the second lane from at least one previous trip along the roadway.
 6. The system of claim 4, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane; and the at least one processor is configured to determine, while the vehicle is traveling in the first lane and the first precision is below the threshold, that lane markings of the first lane are not sufficiently detectable by the at least one sensor to demarcate the first lane; and select the second lane based on information that lane markings of the second lane sufficient to demarcate the second lane are detectable by the at least one sensor.
 7. The system of claim 4, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane; the first lane is a preferred lane for at least a current segment of a route that the vehicle is following; and the at least one processor is configured to: subsequent to maneuvering the vehicle to the second lane, determine if lane markings are detectable in a nearby segment of the first lane while the vehicle is in the second lane, and maneuver the vehicle from the second lane into the first lane when the lane markings are available in the nearby segment of the first lane.
 8. The system of claim 4, wherein the at least one other localization reference comprises a signal from at least one GNSS satellite that is detectable by the at least one sensor while the vehicle is in the second lane.
 9. The system of claim 8, wherein the processor is configured to determine the location of the vehicle with a second precision while the vehicle is travelling in the second lane; the first precision is based on a first number of GNSS satellite signals that are detectable by the at least one sensor; and the second precision is based on a second, larger number of GNSS satellite signals that are detectable by the at least one sensor.
 10. The system of claim 8, wherein an obstruction near or on the road prevents the at least one sensor from detecting a signal from the at least one GNSS satellite while the vehicle is travelling in the first lane; and the at least one processor is configured to maneuver the vehicle into the second lane to increase a distance between the vehicle and the obstruction.
 11. The system of claim 10, wherein the at least one sensor detects the obstruction; the at least one processor is configured to determine a position of the obstruction relative to the vehicle; and the at least one processor is configured to select the second lane based on the determined position of the obstruction relative to the vehicle.
 12. The system of claim 8, wherein the at least one processor is configured to select the second lane to increase a number of GNSS satellites detectable by the at least one sensor from a first number while the vehicle is traveling in the first lane to a second, larger number while the vehicle is traveling in the second lane based on at least one of ephemeris data regarding positions of GNSS satellites and data regarding obstructions along the roadway that may interfere with the at least one sensor detecting at least one of the GNSS satellites.
 13. The system of claim 1, wherein the first precision is based on a first amount of localization reference information while the vehicle is traveling in the first lane; and the at least one processor is configured to select the second lane based on a determination that, while the vehicle is traveling in the second lane, determining the vehicle location will be based on a second, larger amount of localization reference information that provides a second precision that is better than the first precision.
 14. A computer-implemented method comprising: while a vehicle comprising at least one processor and at least one sensor is traveling in a first lane of a roadway, determining, using the at least one processor, a location of the vehicle with a first precision based on at least one localization reference; determining that at least one characteristic of the first precision is below a threshold; and based on the at least one characteristic being below the threshold, maneuvering the vehicle, using the at least one processor, to a second lane of the roadway.
 15. The method of claim 14, comprising determining, using the at least one processor while the vehicle is traveling in the second lane, the location of the vehicle with a second precision, wherein the at least one characteristic of the second precision is above the threshold.
 16. The method of claim 14, wherein the at least one localization reference comprises lane markings sufficient to demarcate the first lane and the at least one characteristic corresponds to a presence of the lane markings; or the at least one localization reference comprises a GNSS satellite signal and the at least one characteristic corresponds to a number of GNSS satellite signals.
 17. The method of claim 14, comprising selecting the second lane based on information regarding at least one other localization reference that is detectable by at the least one sensor while the vehicle is in the second lane but not in the first lane.
 18. The method of claim 17, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane; and the information comprises at least one of an output from the at least one sensor corresponding to detecting the lane markings of the second lane, predetermined map information regarding lane markings in a vicinity of the determined location of the vehicle, and predetermined information regarding the lane markings of the second lane from at least one previous trip along the roadway.
 19. The method of claim 17, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane and the method comprises determining, while the vehicle is traveling in the first lane and the at least one characteristic of the first precision is below the threshold, that lane markings of the first lane are not sufficiently detectable by the at least one sensor to demarcate the first lane; and selecting the second lane based on an indication that lane markings of the second lane sufficient to demarcate the second lane are detectable by the at least one sensor.
 20. The method of claim 17, wherein the at least one other localization reference comprises lane markings sufficient to demarcate the second lane; the first lane is a preferred lane for at least a current segment of a route that the vehicle is following; and the method comprises: subsequent to maneuvering the vehicle to the second lane, determining if lane markers are detectable in a nearby segment of the first lane while the vehicle is in the second lane, and maneuvering the vehicle, using the at least one processor, from the second lane into the first lane when the lane markers are available in the nearby segment of the first lane.
 21. The method of claim 14, wherein the at least one other localization reference comprises a signal from at least one GNSS satellite that is detectable by the at least one sensor while the vehicle is in the second lane.
 22. The method of claim 21, comprising determining, using the at least one processor, the location of the vehicle with a second precision while the vehicle is travelling in the second lane and wherein the first precision is based on a first number of GNSS satellite signals that are detectable by the at least one sensor; and the second precision is based on a second, larger number of GNSS satellite signals that are detectable by the at least one sensor.
 23. The method of claim 21, wherein an obstruction near or on the road prevents the at least one sensor from detecting a signal from the at least one GNSS satellite while the vehicle is travelling in the first lane; and maneuvering the vehicle into the second lane comprises increasing a distance between the vehicle and the obstruction.
 24. The method of claim 23, comprising: detecting the obstruction using the at least one sensor; determining a position of the obstruction relative to the vehicle using the at least one processor; and selecting the second lane based on the determined position of the obstruction relative to the vehicle.
 25. The method of claim 21, comprising selecting the second lane to increase a number of GNSS satellites detectable by the at least one sensor from a first number while the vehicle is traveling in the first lane to a second, larger number while the vehicle is traveling in the second lane based on at least one of ephemeris data regarding positions of GNSS satellites and data regarding obstructions along the roadway that may interfere with the at least one sensor detecting at least one of the GNSS satellites.
 26. The method of claim 14, wherein the first precision is based on a first amount of localization reference information while the vehicle is traveling in the first lane; and the method comprises selecting the second lane based on a determination that, while the vehicle is traveling in the second lane, determining the vehicle location will be based on a second, larger amount of localization reference information that provides a second precision that is better than the first precision.
 27. A system for controlling a vehicle, the system comprising: at least one sensor configured to detect at least one localization reference; and a processor configured to determine that at least one obstruction near the vehicle is preventing the at least one sensor from detecting the at least one localization reference while the vehicle is traveling in a lane of a roadway; and based on the determination, alter a speed of the vehicle while in the lane to change a position of the vehicle relative to the obstruction until the obstruction no longer prevents the sensor from detecting the at least one localization reference.
 28. The system of claim 27, wherein there is a preferred speed of the vehicle on the roadway; the altered speed of vehicle differs from the preferred speed; and the processor is configured to further alter the speed of the vehicle to correspond to the preferred speed after the obstruction no longer prevents the sensor from detecting the at least one obstruction.
 29. The system of claim 27, wherein the at least one obstruction comprises at least one other vehicle traveling along the roadway.
 30. The system of claim 29, wherein the at least one obstruction comprises two vehicles; a first one of the two vehicles is on a first side of the vehicle; a second one of the two vehicles is on a second, opposite side of the vehicle; and the processor is configured to determine that the processor cannot maneuver the vehicle into an adjacent lane on the roadway while the first one of the two vehicles is on the first side and the second one of the vehicles is on the second side of the vehicle. 